Electromagnetic drilling control for rotary drilling rigs



De@ *1, 1931 E. P. BLANKENSHIP ET A1. 1,834,894

ELECTROMAGNETIC DRILLING CONTROL FOR ROTARY DRILLING RIGS Filed Aug. 25, 1930 2 Sheets-Sheet 1 Decl, 1931. E. P, BLANKENSHIP ET AL 1,834,894

ELECTROMAGNETIC DRILLING CONTROL FOR ROTARY DRILLING RIGS Filed Aug. 25, 1930 2 Sheets-Sheet 2 Cllfozun'lt Patented Dec. 1, 193i :UNITED STATES PATENT ori-ICE EARL P. BLANKENSHIP AND FRANK E. BROCK, OF SEMINOLE, OKLAHOMA ELECTROMAGNETC DRILLING CONTROL FOR ROTARY DRILLING RIGS Application led August 23, 1930. Serial No. 477,418.

This invention relates to brake controlling lneans for rotary oil or gas well drilling rigs, though not, of course, limited thereto, and particularly to brake means for regulating the feed and weight carried on rotary drilling bit.

One of the objects is to provide a construction of this character including a solenoid operatively connected to the brake lever and operating against the drag spring of the brake lever whereby, under certain circumstances, the magnetic controlling device will be operated to release the brake, letting oit the drill pipe to a predetermined amount of weight desired, the circuit through the magnetic controlling means being then broken and the drag spring then operating to apply the brake and hold the draw-works at this oint.

A further object is to provide an electromagnetic control oi" this character operating in connection with an indicator, and a circuit controller and the usual dead line.

A further object is to provide a solenoid, one end of which is constructed to form a dash pot within which the core or plunger of the solenoid operates.

Other objects have to do with the details of construction and arrangements of parts as will appear more fully hereinafter.

Our invention is illustrated in the accompanying drawings, wherein Figure 1 is an elevation of a winding drum for oil well drilling rigs having a brake and brake lever with my invention applied thereto, the controlling means for the solenoid being diagrammatically shown;

Figure 2 is a sectional view of the solenoid;

Figure 3 is a sectional view of the tap for the solenoid.

Referring to these dra-wings, 10 designates the brake drum of a draw works to which a rotary drilling line 11 is attached. `We have not illustrated any more of the draw works than the brake drum nor any of the rotary well drilling mechanism, this being wellknown.

Coacting with the brake drum is the usual brake band 12 operating by means of a lever 13 of the usual type so that when this lever is depressed, the brake is put on and when the lever is raised, the brake is released. For the purpose of urging the brake to its on position, the usual drag spring 14 is provided which engages the tree end of the brake lever. So far we have stated the parts which are found in practically all draw works. The purpose of our invention, as before stated, 1s to control the rotary drum of the draw works to which the rotary drilling line is attachcd, controlling the drill stem and drill bit carried by Jthe line. To this end, we provide a solenoid designated 15 which is supported in any suitable manner, as Jfor instance, upon the bracket 16 on the derrick or frame of 65 the draw works or in any other suitable position. This solenoid is provided with an outer shell or housing designated generally 15 with the usual core or plunger 17 and the coil 18. A stop strap 19 is attached to the lower end of the housing and forms a stirrup through which the reduced end 20 of the core 17 passes, thus limiting the downward movement of the core. rlhe upper end of the core is provided with a leather cup 21 itting the inside of a. brass liner 22 mounted within the cup and held upon the plunger by a screw 23.

Extending from the closed end of the housing is a pipe 24 provided with a check valve 25 and with an air entrance opening 26 controlled by a tap 2'?. This tap may be closed to any desired extent. When the plunger or core moves downward under the action of the spring 14, air will be drawn in through the check valve into the upper end of the housing above the plunger and when the plunger moves upward under the action of the solenoid, the air within the upper end of the housing is compressed, but the air is gradually forced out through the tap 27, thus checking the upward movement of the core and checking the operation ot the brake so that the brake will be released relatively slowly at the last portion of its movement. The plunger is connected to a turn buckle 28 by any suitable means and this turn i buckle in turn is connected by suitable linkage including a spring 29 to the brake handle 13 at any desired point. It will be obvious now thatV when the solenoid is energized the core will be drawn upward and the brake re- When the tension on the dead line increases,

thel roller 34 will be forced inward, thus causing the fluid within the casing 33 to be compressed. This casing 33is connected by a small tube 35 to a tube 36 having in its length the pressure indicator 37. 'lhis tube extends to a Vernier controller 38 of ordinary make. The pressure which it is desired to carry on the bottom of the hole is set by means of the vernier. When this pressure reaches the amount to which the Vernier h as been set, the Vernier operates to close a c1r cuit through a relay switch 39 which opens a circuit through the wires 40 leadlngwto the solenoid, thus permitting the drag spring 1 4 to apply the brake. When the pressure d1- minishes to a predetermined amount, theyernier closes a circuit through the relay switch, causing the solenoid to be energized and the brake 12 released.

Thus the feed and Weight carried on the rotary and drill bit during the drilling operation are at all times automatically controlled. lVhen the pressure is raised to a set pointpn the indicator, the magnet is energized which raises the brake lever, letting off thel drill pipe to a predetermined amount of weight desired which will break contact in the controller, .thus breaking the magnetic circuit.

Then the drag spring again sets the brake,

stopping the downward movement of the drill pipe.

The dash pot formed by the upper end of the solenoid housing permits the core to drop downward rapidly, but checks or cushions the upward movement, the pet cock being adjusted to the amount of compression it is desired to carry in the upper end of the hous- It will be understood that we have illustrated in the drawings, one make of Weight indicator composed of parts 32-34 and We do not wish to be limited to this. The Vernier 38 is set to the amount of weight desired to carry on the bit and as the bit drills olf the weight increases causing the indicating hand on the Vernier to make contact andenergize the magnet in order to feed ofl'. As bit and drill stem are fedy ofl the weight is lightened., causing reverse movement of indicating hand on vernier-which makes Contact to release magnet. Obviously various forms of controlling means embodying the principle of4 this invention might be used.

We claim 1. In combination with the brake of a r0- tary drilling rig,.the brake including a brake band, a brake lever and a drag spring urging the lever in a direction to apply the brake, of means controlled by the weight on the drilling bit of the drilling rig acting to release the brake when the Weight on the drilling bit exceeds a predetermined amount including a solenoid coil acting, when Venergized, in an opposite direction from the drag spring, a core therefor operatively connected to the brake lever, a housing enclosing the solenoid and extending over the upper end thereof, the core having a cup engaging the interior wall of the solenoid and acting as a piston, the closed end of the housing having an inwardly opening check valve and having an adjustable vent whereby to check the inward movement of the core of the solenoid, the housing having a stirrup through which the core of the solenoid passes limiting the outward movement of the core.

2. In combination with the brake of a rotary drilling rig including a brake band, a brake lever and means urging thepbrake lever into a brake applying position, electro-magnetic means for releasing the brake from a braking position including a solenoid coil, a core therefor, a dash pot having therein a piston operatively connected to the brake and yieldingly resisting the movement of the brake toward a releasing position, a turn buckle connected to the core and to the brake lever, and means controlled by the Weight on the drill bit of. the drilling rig acting to energize the solenoid to Agradually release the brake when the weight exceeds a predetermined amount.

3. In combination With the brake of a rotary well drilling rig, including a brake band, brake lever and means urging the brake lever into a brake applying position, electro magnetic means for releasing the brake from a braking position including a solenoid coil, a core therefor operatively connected to the brake lever, means controlled by the weight of the drill bit acting to energize the solenoid when the weight increases beyond a predetermined amount to thereby release the brake, and a dash pot having therein a piston operatively connected to the brake lever and yieldingly resisting movement of the lever toward a releasing position, the dash pot hav,- ing an outlet vent and beyond the vent an inwardly opening check valve.

In testimony whereof We hereunto aiiix our signatures.

. EARL P. BLANKENSHIP.

FRANK E. BROCK. 

